Muffle-furnace.



CJ. mRsELL.y

MUFFLI FURNACE.

APPLICATION FILED JUNE 4| ISIQ.

Lzg?, Patentedl Feb. 25, v1919.

2 SHEETS-SHEET 2.

f gmx lNVEN GR.

CARL T. TORSELL, OF WARREN, OHIO.

MUFFLE-FURNACE.

Specication of Letters Patent. Patented Feb, 25', 1919,

Application led .Tune 4, 1914. Serial No. 843,015.

To all 'whom z't may concern:

`Be it known that I, CARL T. ToRsnLL, a citizen of the United States, and resident of Warren, in the county of Trumbull and State of Ohio, have invented a new and useful Improvement in Muffle-Furnaces; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to muflie furnaces for treating metals, such as by carbureting or case hardening steel or iron bars and plates. The ordinary furnaces employed forV this purpose have the heat or flame in direct contact with the walls inclosing the material within the muflie which is built within or movable within the heating chamber and it is found that because of the difference in the application of heat to the material inclosed within the muftle chamber, such as the plates or bars of steel or iron separated by suitable carbureting material such as charcoal or coke or mixtures thereof, different parts of the material are carbureted to dierent depths according to the heat developed in the particular parts of the muflie chamber which is being heated higher than other portions thereof. The object of my invention is to provide for the even distribution of the heat around the inutile chamber and in that way to obtain a substantially even distribution of heat within the chamber, and a more even heating and carbureting or case hardening of the materials.

The invention consists generally stated in a muiile furnace having inclosing walls forming the muiiie chamber adapted to contain the material to be treated, and around such muffie chamber inclosing walls forming a closed space for air or other suitable iluid for the circulation and distribution of the heat of the furnace to the muiie chamber. It also consists in other improvements, as hereafter described. Y

In the accompanying drawings, Figure l is a longitudinal section of a Inuiiie furnace embodying the invention, tlie section being formed on line 1 1, Fig. 3. Fig. 2 is a like View, the section being formedon the line 2*-2, Fig. 3. Fig. 3 is a cross sectlon of the yfurnace on the line 3 3, Fig. 1; Fig. 4 isa horizontal section of a portion of furnace showing the spread walls. forming the muiile and surrounding chamber; and Fig. 5 is a cross section of one of the muiiies showing more clearly the continuous inclosing air space around the mums.

`partially closed by suitablebricks 9, as desired, `to regulate the heat so that part 'of it ,passes through the furnace above the port,

through said port 8 into the stack. Within this heating chamber is built the muflle cham- .ber around which heat is caused to circulate .1n any desiredway, the furnace illustrated simply-representing one good Wayof applying thesheat in a coal fired furnace. In the construction illustrated the piers 10 separate the lower horizontal fines 3, said piers extending for the length of the furnace, and supporting the muiilesll separated by the longitudinal flues .7 above referred to. f This muftle chamber 11 vis made lof any desired length and isarranged' to be closedduring the cementation or carbureting action as by the bricking up of thejport 11a at the opposite `end of the furnace from the stack 6. For the lbuilding of themuiile any suitable material may be employed. I prefer, however, to employ a series of tiles which will provide the muffie chamber to receive the bars and plates or other material to be treated and around the same the inclosing airspace 12, this being accomplished by the tiles, as illustrated in the drawing; for exam le'the tileslf rest upon the piers 10, such ti e having the recesses -14 forming the lower portion of the air spaces and having side recesses 14a, while the tiles 15 rest upon the tiles r13 and inclose the longim tudnal recesses 14 extending under the muffle chamber for .its full length and provide the vertical ports 16 leading upwardly through the tiles, as shown in the several figures.

Resting on the tiles 15 are the tiles 17 forming side walls of the muilie chamber, and out.- side of said tiles and inclosing the same are the tiles'lS whichr with-the tiles 17 form the vertical air channels 19 leading up to the and communicating with the side recesses 22j leading to the longitudinal recesses 22 in the upper roel' tiles 23, which extend over the top et' the niuiiie chaiiiber. Thus 1 ain eiiabled to provide around the niuiiie chambers 11, the continuous inclosing air space 12 Within Which the inclosing air can`cireulate and distribute its heat through the walls of Athe `inutile chamber to vthe iiiaterial therein. i The space 12mhas` 'no communication vwith the atmosphere and is purelyf'otan insulatiiig character. The several tiles thus vreferred tear iiade Asuitable sections 'and are pref- `eraloly iittedftogether bytoi'igu'e and groei/e y "s, I"so hat 'iyli'eii the in iiflies are Qbuiltjuliacontinuous irrouiiding and inclosfed Aair space pioif'ii. editor lthe length of f'eaelii iiiiiftle ""'The' c'oier tiles 20 and 23 are illustrated as joinedv byiyedge tiles 24, which kforni?"theroofpo tions' ofr'the longitudinal es and through the safineare l:torined fthe vports "lea-diiigtothe top Hue spaces around the niuilie's.

"siitable onguesj y'seated in grooves 26y o n ftlietop {lool-tiles which these longitii`cl iii`al"`ti`les'17` and 18 are easily heldto p Ov per distance to 'forni the longitudinal air A slicel Z i tlieyhiaiie like tongues engaging 'ii ithferoofs'iii the loiyl'ereoyer'tile20- VThe seyeral ls'eetioi'is of tiles are also preferably eonneted by'f'rtongueand giioore `ioints along` "ieredgessucliastlie ftoiigue and groove oiiits 2 iidSO, shown iii F ig." L I: draiiii'ig's also show the Vertical feedoiits'" `31S-eXtei'idiiig down "through the oef @Qliy iyliiclifthe g'round niixtiire of joliaieal'," colret'oi other carbureting inayYterial eanilbefed in'iilliiig lthe inuiie with plates er'rb'ais 'oriotlier artielesto be treated.

so j

chambers are charged iii aiiysuitable Way' in A iat'ejplatesf o iwib'ar's" or in "packages through oifitswsueh as ,the yports 11,'slioj\ vii layers carburetiiig in'aterial beille'd viii@loetweeifftlieiii, sii-cli through i. ,g'irlsidlfs" 31, the Plates tofb@ liarged-"restiiig o i'ithc sa ine,'an`d :further Ofelia oal' or other carbureting inaterei-bang spear uan the' tiene t'f'iriiothe"layen of plates are put iii place, the iiiuiliefbeingtliiis filled up Ito its top cover. 50 oth s of"ii atal to' b. case hardened, 'oelriient'ed of e bit aroused, `the car tir ti is`v suitably distributed 'ove "'r nd the v surfaces thereojl` as d dif' A' The charging openings: are then "up "ivitlibrickjifork aiidsteel, as are f iging f uiinels' eXtendii'igtlirough th of'so the`iiiiie chambers. A'coiitiiiuou'sf-hleatfis appliedto tlieln'iuiiies for s uiiich eSlQm Steenlo thirty gto'tlie carburization or ceini desired.`r Prtofthe heatis ciriii" the' "rigenerate invention the' inutile lell'itiles' recesses tlferoin Vvthedistribution of the heated products being according to the desired heating of the furnaces, whicli can be Watched by suitable ports or peep holes. The heat applied passes through 'the outer inclosing tiles, such as through the Walls 13, 18 and 23 and heats the air Within the continuous. iiiclosed air space 12, lthe air tlierfeiiil circulating according to the heat developed, and thenfpeiietrating tlfrougli the inner Walls forming the iiiuiile cli'aii'il'ier 'itselfffor exainple"` through the tiles .15','1`7'aiid 201 lThus aiiereii distribution of heat is obtained Within theE iiiju'iiie -ch'iiiiber throughA the circulation 4oi the lieat Wit-hiii tliefiifi'clos'ed air space' Vinstead of' the in uiiie chamberl Walls by direct Contact Withthe Haine y and heated productsof ycombustion u'fitli the muiilech'ainbein As the heat passes through 'the outer Walls, it is radiated lin ally directions spreading` Within the inclosiiig air space, and 'there is'oppoi'jtiinity' foi'sueli Idistribution of the heat therein tlirouglntlie oircul'ationfof the air ivitliiii the chamber', a practically 'even distribution ofdtlietlieat through the in'closfingffwalls of Athe n 'iuiiie chamber, and a practically: eren heating of the contentstherein, causing a niu'cliinore vevenl and fuiiiforincenieiitiiig or Ica rburizing ofthe 'iiiaterial tli'e inuiiie'clianiber, and tliu's insuring practicallyv iiiiifoifin earburiation tothe diifei'ent plates or Aother i'iietal bodiesy subjected to tlie'tre'atnient.'

In this operationWhere voneJ aiftof the outer inclosin'g Wallsvof the in e ini'glit'be 'subieeted'tow-higher heat; this "Willv not iii.

j uriousl'y affeet the 'heating of the "nia'terials Within the ii'ii'i'ifle because vthe heat passinfo-th roiig'li 'the outer tiles or Walls separates proper. There 'is also a ylongi'tiitlinal"circutiiiuo'us'slots or ports iorii'iiii'g'tlie continuous air space around ther inuflie elianiber proper. Iain enabled thus to produce iiiofre u'nili'orinly treated plates and oi'ercorne' the diiiiculties heretofore encountered lriiitli fuiiiaces Where there was 'over Carburi'z'atioii of Vs'oiiie p artsoi the charge `and uiider-Carburi- "Lationinr others. i i l' IW "Wliat `["`claim' is:

iiiiiHle'iiiiIaCe having a pier extending longitudinally therethrough, aiidliaiiig a inutile chamber' formed of tile, the ylc'io tom Iof 'said eliaiiiber Y being'fforiiedffof .two paralspace in the bottom wall oi. the chamber and the top wall oi the chamber being formed of two parallel tiles having recesses therein forming an air chamber above the mule chamber, said several spaces being connected to form a closed insulating fluid space around the muie chamber for distributin the heat of the furnace within said muiiie c amfber.

2. A inutile furnace having a pier extending longitudinally therethrough and having a niuiilechamber formed of tiles or brick, the bottom of said chamber being formed of two parallel tiles having recesses therein forming together a longitudinal air space below the chamber, the said walls being formed of two parallel tiles forming air spaces and the top wall of the chamber being formed of two parallel tiles having recesses therein formin an air chamber above the muiile chamber, sald several spaces being connected to form a closed insulating iuid space around the muiie chamber for dis-y tributing the heat of the furnace within said muie chamber, said several tiles having tongue and groove connections to hold them in place.

3. A. muiie furnace having heating chamber, and a series of piers extending therein and a series of muie chambers supported on said piers each of said muiie chambers being formed oi. tiles which provide closed insulating fluid spaces around each muiiie chamber, and the top or cover tile being connected by wedge tiles to form the roof of the heating chamber of the furnace.

In testimony whereof, I the said CARL T. ToRsELL, have hereunto set my hand.

CARL T. TORSELL.

Witnesses:

JOHN F. WILL, J. R. KELLER.

Copies of this patent may be obtained forvve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

